32.80 miles [1]; serving Birmingham, it loops I-59 to the south.
Interstate 459 was originally planned as "Interstate 59B," but this designation
was changed to 459 before the highway was built. [3]
It was completed in 1984. [10]

Most of Interstate 459, except a short section near I-20/59, was built
as a six-lane bypass with a grass median. In the early 1990s, Alabama
paved over the median, not to add lanes, but merely leave wider
left-hand shoulders and the Jersey barrier. This implies that the state
plans, once it widens the bridges, to make I-459 eight lanes. [2]
[3]

The plans for I-459 date back at least 35 years. Hearings were held in
May 1961, September 1966, and October 1968 to resolve local objections
to routing. The original plan was a complete loop around Birmingham; in
its stead, business and "white flight" have left the city for points
along the bypass. Apparently county and surrounding city funds were in
place for the north loop, but Birmingham itself, saddled with some
ethical problems, could not come up with its share. [4]

Northern Beltline planned to complement I-459

The mirror image of I-459, a 51-mile northern Birmingham bypass, is
one of the ISTEA/NHS "High Priority Corridors."
[3] As of late 2001, right-of-way was being purchased in this area. [5]
However, it's not definite whether this road will also be signed I-459. [7]

4.50 miles [1]; Short spur in Gadsden from I-59 to Rainbow Drive.
Interstate 759 opened between 1985 and 1989.
In 1999, the Alabama legislature designated I-759 the Joe Ford Expressway.

The presence of I-359 (Tuscaloosa) and I-759 (Gadsden) would imply that Alabama
once planned an Interstate 559, perhaps in Birmingham; however,
ALDOT says there's no such thing as I-559, former, future, or secret.

Two extensions planned

Plans are afoot to extend Interstate 759 in both directions:
northward/westward to US 431 west of Attalla [6];
and eastward to George Wallace Drive, eventually to US 431/278. [8]
This would change the role of Interstate 759
from an I-59 spur to a US 431 bypass.

In March 2004, the Gadsden-Etowah Metropolitan Planning Organization (MPO)
formally endorsed the I-759 West proposal, adding it to the 2025 long-range plan.
The extension, already proposed in 1990, would relieve congestion caused by
commercial and industrial growth. Cost might be around $70 million. [9]